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2ProgramsA program is a set of step-by-step instructions that directs the computer to do the tasks you want it to do and produce the results you want.

3Programming LanguagesA programming language is a set of rules that provides a way of telling a computer what operations to perform.

4What Can a Program Do? A program can only instruct a computer to:Read InputSequenceCalculateStore dataCompare and branchIterate or LoopWrite Output

5Sequence Control StructuresSequence control structures direct the order of program instructions.The fact that one instruction follows another—in sequence—establishes the control and order of operations.

6Calculate Add 1 to CounterA program can instruct a computer to perform mathematical operations.Add 1 to Counter

7StoreA program will often instruct a computer to store intermediate results.Place 1 in Counter

8Compare and BranchA program can instruct a computer to compare two items and do something based on a match or mismatch which, in turn, redirect the sequence of programming instructions.There are two forms:IF-THENIF-THEN-ELSE

11IterateA program loop is a form of iteration. A computer can be instructed to repeat instructions under certain conditions.No

12Iteration Control StructuresIteration control structures are looping mechanisms.Loops repeat an activity until stopped. The location of the stopping mechanism determines how the loop will work:Leading decisionsTrailing decisions

13Leading DecisionsIf the stop is at the beginning of the iteration, then the control is called a leading decision.The command DO WHILE performs the iteration and places the stop at the beginning.

15Trailing DecisionsIf the stop is at the end of the iteration, the control mechanism is called a trailing decision.The command DO UNTIL performs the iteration and puts the stop at the end of the loop.

17Programs are Solutions to ProblemsProgrammers arrive at these solutions by using one or more of these devices:Logic flowchartsStructure chartsPseudocodeStructured Programming

18Logic FlowchartsThese represent the flow of logic in a program and help programmers “see” program design.

19Common Flowchart SymbolsTerminator. Shows the starting and ending points of the program. A terminator has flowlines in only one direction, either in (a stop node) or out (a start node).Data Input or Output. Allows the user to inputdata and results to be displayed.Processing. Indicates an operation performed by the computer, such as a variableassignment or mathematical operation.Decision. The diamond indicates a decision structure. A diamond always has twoflowlines out. One flowlineout is labeled the “yes” branch and the other is labeled the“no” branch.Predefined Process. One statement denotes a group of previously defined statements.For instance, “Calculate m!” indicates that the program executes the necessary commandsto compute m factorial.Connector. Connectors avoid crossing flowlines, making the flowchart easier to read.Connectors indicate where flowlines are connected. Connectors come in pairs, one witha flowline in and the other with a flowline out.Off-page connector. Even fairly small programs can have flowcharts that extend severalpages. The off-page connector indicates the continuation of the flowchart on anotherpage. Just like connectors, off-page connectors come in pairs.Flowline. Flowlines connect the flowchart symbols and show the sequence of operations during the program execution.Common Flowchart Symbols

21Structure ChartsStructure charts illustrate the structure of a program by showing independent hierarchical steps.Major divisions are subdivided into smaller pieces of information.

22PsuedocodeThis device is not visual but is considered a “first draft” of the actual program.Pseudocode is written in the programmer’s native language and concentrates on the logic in a program—not the syntax of a programming language.

24Structured ProgrammingStructured program languages lend themselves to flowcharts, structure charts, and pseudocode.Structured programming languages work best where the instructions have been broken up into small, manageable parts.

25The Program Development CycleAnalyze the problemDesign the solution algorithmDesign the user interfaceWrite the codeTest and debug the programComplete the documentation

29High-Level Languages Higher Level Languages 4GLsUse traditional programming logic where the programming instructions tell the computer what to do and how to perform the required operations.4GLsUse high-level English-like instructions to specify what to do, not how to do it .

34Programmer’s LingoProgram - detailed set of instructions for a computerProgramming Language - tool used to create a program; defined by semantics and syntaxSemantics - the meaning of words in a languageSyntax - rules for combining symbols of a language